System of electric welding



D. H. WILSON.

SYSTEM 0F ELECTRIC WELDING.

APPLICATION FILED IuIIE I2. 1916.

Patented M31'. 9,1920.

3 SHEETS-SHEET I.

E USM :IL/OMM E dfiw D.'H. WILSON.`

SYSTEM 0F ELECTRIC WELDING.

APPLICATION FILED JUNE I2. 1916.

Patented Mar. 9, 1920.

3 sHEETs-sHeET'z.

4 7l JNVENTOR.

J BY 47km 75M ATTORNEYS.

D. H, WILSON,

SYSTEM 0F ELECTRIC WELDING. APPLICATION FILED 1uNE'12. 191s.

l Patented Mar. 9, 192.(1A

vA TTORNEYS.

- UNITED sTATEs PATENT. oEEIoE.

DAVID H. WILSON, 0F- FRANKLIN TOWNSHIP, BERGEN COUNTY, NEW JERSEY.

y 'SYSTEM OF ELECTRIC WELDING.

specification of Letters Patent. Patented Mar. 9, 1920.

Application led .Tune 12, 1916.v Serial No. 103,157.

'0 all whoma't 'may concern Be it known that I, Darm H. WILSON, a citizen of the United States, and resident of Franklin township, in the county of Bergen and State of New Jersey, have invented cer,- tain new and useful Systems of Electric Wfelding, of which the following is a specication. V My invention relates to electric welding with an arc. It comprises a method of andy s from the tool to the metal to be welded.

Such hand operated tools vary in their 'distance from the metal being welded with the result that the are has to travel across a space which varies in its resistance, and consequently this varies the amperage of the current. This variation results in irregularity and porosity in the weld.

The object of my invention is to maintain a somewhat even amperage regardless of the resistance and space across which the arc has to travel in making the weld.

In other words my invention tends to olfset and counteract the irregularity of the manual manipulation of the welding` tool,

- and thus avoid the porosity due to an irregular deposit of Welding metal. This is of particular value when the electrode itself supplies the welding metal with which the welding is accomplished, the irregular current and heat causing an irregular iiow of metal across the arc. o

Figure 1 shows a diagram view of my in-y vention.

Fig. 2 shows a front elevation of another form of my invention.

Fig. 3 shows the circuits thereof in diagram. v

Fig. 4 is 'a section of a detail. A

In Fig. 1 two portions of''netal 1 and 2 are shown havingl a4 crack 3 adapted to be welded` by means of the welding tool 4. The welding tool is held by an insulating handle 5,and is normally connected to a conductor 6 leading'to a generator or other `source of current 17 over the following circuit; conductor 7 magnetic coil 8, shunt 8 1n multlple therewlth, .resistance 9 and solenoid coil 1() to conductor 6. When the tool 60 4 is touched to the metal at 3 a current passes overk thls circuit wh1ch shouldhave a m1n1' mum welding .volume of perhaps about 25 `amperes at to 75 volts. The initial circult automatically closes the .open pair of contacts 11 held normally open by the spring 12 adapted to close branch circmts arranged' to deliver an additional amountof current toy the welding tool. The first of these branch circuits may be traced from the conductor 7 70 through the closed pair of contacts 11', closed by magnet 8 whenenergized, the armature 13, conductor 14:, rheostat 15, conductor 16, thence through the line conductor G to the source of current indicated at 17. The

rheostat 15 is designed and constructed to be operated by hand and may be set in .a number of positions for the purpose of arbit-rarilye fixing the major amount of current intended to be delivered to the tool 4 forth@ 8,0

particular welding operation in hand. The arm 18 of the rheostat may be swept over the contacts 19 .to introduce such-variable resistance as will permit the passage of say 25 or 50 or 75 or 100 or 125 amperes, as may 85 be desired.

A second branch circuit is also established by the circuit closer 8 which may be traced as follows; conductor 7, contacts` 11, armature 13, conductor 20. circuit breaker 37, confductor 20, the variable resistance 21 of the automatic rheostat, arm 22 of the rheostat,

conductor 23. conductor 25, solenoid 10. conductor 6 and generator 17 This branch circuit just traced may introduce a variable re- .sistance between the tool 4 and the weld 3.

This resistance at the tool varies to such an extent as would tend to vary the amperagc by an amount from zero to 15 amperes or more. therefore have the resistances between its points4 so adjusted as to compensate to a considerable degree for the variation at the tool. The arm 22 of the automatic rheostat is lturned upon its pivot 26 by means of the 105 core 27. of the solenoid which is operatively connected to the arm 28 of thelever by the pin and slot 29. The core 27 is normally re- .l tracted tothe position shown in the drawing by means of the coil spring` 30.. one' end 110 of which is secured to the projection 34 of the core 27 and the other end secured to a.

The variable resistance 2 1 should 100 the conductor 20 to the tool 4. If the re- 21 of the variable resistance until the pull of the solenoid coil balances the increasing pull of the spring 30 after which the arm 22 comes substantially to rest. If the resistance between the tool 4 and the welding 3 increases, it causes a reduction of current in the solenoid 10 which permits the spring 3 to retract the core 27 thereby reducing the resistance at 21 and thus maintaining the even iiow of the current through sistance at the tool is decreased a stronger pull upon the core 27 is exerted by the solenoid 10 thereby automatically introducingl a greater portion of the resistance 21 intov the circuit with the tool thereby also maintaining the even flow of current through the tool.

When the tool 4 is first applied to tlie weld' it is desired to prevent a rush of current over the resistance 21. If the arm 22 under the tension of spring 30 rested 011 the lowest resistance point 21, such a rush would occur, and the fused metal would' be splashedfaround. To prevent this a solenoid 36 is introduced in a normally closed circuit bridged across the line conductors 6 and 35 to hold the arm 22 in thel position to introduce a. considerable resistance into the circuit of the tool 4 until the solenoid coil 10 exerts its balancing influence upon theautomaticl resistance varying device 21. The current through the' solenoid l() flows also through the coil 37 and opens the conf tacts 38 held normally closed by spring 39 at the same instant that the solenoid eX- erts its balancing pull on the core 27. The arm 22 sweeps over ithe resistance 21 reducing the amount of resistance in the circuit until thebalance is established.

The line conductors 6 and 35 may supply a current of say volts and from 100 to 500 amperes, and the resistance rheostat may vary frornOto about 2 ohms or more. The shunt 8 may `pass the greater porj tion of the welding current about the'oircuit closer magnet 8.

lIt wlll be noted that when the welding tool 4 is brought into contact with the work` current rst flows through the branch 25 thereby' closing the contacts 11 and intro-1 ducingiv the adjustable resistance 21 which builds up the current required for drawing the arc.

An additional adjustable rheostat -15 is employed adapted to be adjusted as to its resistance and adapted to complete the welding circuit when the current flows through the welding tool. The amount of resistance reduction depends upon the position of' the rheostat switch arm I8 and the means for removing an adjustable portion of the resistance from the circuit consists in the conductors 16 and 14 which are brought into the welding circuit bv the contacts, 11.

Suitable apparatus well known to engineers may be employed in placeofthe diagrammatic apparatus shown.

Any kind of heating'current suitable for welding may be employed, and the main purpose of myA invention is to secure an even heat in the arc, regardless of the re sistance of the arc or of the character of the current.

Another form of my invention is s hown in Fig. 2. In this figure is shown a back board or panel '45 upon which are mounted various electrical and mechanical devices. vUpon the left hand side of this panelis shown a carbon pile 46. This pile -is/,composed of plates or disks of carbon mounted between a top iXed abutment at 47 mounted on the bracket 47a and the bottom plate 48, each adapted to receive an electrical connection. The pile may, if 'desired be inclosed within a cylinder 49, the inside of which may be covered with a lining of `insulating material, enamel for example, to

a post 50 engaging a lever 51, which is fulcrumed upon an adjustable support; or

screw 52 mounted in the fixedv support 53.

Upon the other side .of the fulcrum aremounted weighs 54 and 55. These weights are adapted to be shifted along the lever to vary the pressure upon the pile. Some of the 'weights 55 may be removed in order to securev the proper pressure upon the pile.

` Set screws 54a may be used to hold them in position. The pressure upon the pile is adapted to be reduced by an electro-responsive device or solenoid shown at 56. Within the solenoid, which is fixed and mounted upon the bracket 57 is a core 58 suitably attached by a link 59 tothe lever 51. During the operation of welding the weldin current passes through the solenoid 56, an

liftsl the core 5'8 thereby lifting-the right hand. end of the lever 51, thereby reducing the, pressure upon the carbon pile 46. A

cuit in multiple with the solenoid 56 for the purpose of adjusting itsstrength and rheostat 60 may be introduced into the cirl for the purpose of adjusting the `.amount ol` current traveling through the solenoid.

The operating circuit ,of these devices is shown more clearly in Fig. 3. A motorgenerator set 61 is preferably employed. It may generate a current having a potential of 60 to 75 volts, or any other suitable current that may be desired. Preferably from4 the positive pole of the generator is conl nected a conductor 62. which is connected to the carbon pile 46, the-other .end of which pile is connected by a conductor 63 through the solenoid 56 and rheostat 60, through the meter and its .shiuit 64, through the conductor'65 to the welding tool., electrode or terminal 66 adapted to be brought into contact with the work 67. The work is connected by a conductor 68 to the negativeterminal of the generator 61. `lllhen the generator is in operation and the welding current traverses the circuits thus described, it passes through the carbon pile and, solenoid and across the terminals 66 and '67 through an arc. The resista-nce of this arc is varied by dierent causes, by the irregularities ot' the,

operators hand during welding, by the distance between the tool 66 and the portions of I the work 67 which an arc may reach, by the coolingeiiect ot' the massof metal at 67, by

the varying temperatures surrounding the.

same, and perhaps b -other causes. As the resistance varies in tlle arc, the tendency is to alter the How of' current across the arc. The moment the current starts tov vary it has a corresponding effect upon the solenoid 56, so that it attracts with greater or less strength, and either reduces orincreases the pressure upon the pile thereby increasing or reducing the resistance of the pile and there- 40 yby reducing or increasing the flow of current through the pile. The joint effects of these various influences is that when the resistance tof the arc increases the rest of the apparatus tends to reduce the resistance of the rest of the circuit to compensate for vthe increasing resistance of the arc, and vice versa, thereby '.maintaining substantially a steady flow of current across the arc, vand thereby -maintaining such a flow ofinetalas to' create aneven and smooth deposit of metal from the metal terminal 66 to the work 67 When the potential of to 75 volts is employed at the generator, the first. contact between the terminal 66 and 67 is apt to create a rush 55 of current and a spattering of Ine-tal that are objectionable. I employ means to prevent it. For this purpose a resistance is introduced into the circuit when the arc is started to prevent this rush of current. This resist- 6e a'nce is introduced by the 'carbon pile 46.

The circuits relating to this function -areas follows.

From the conductor 68, the circuit is led.

through the conductor 69 to the electro-responsive device or solenoid 70 having .a core connected eccentrically to the switch by the link 78. To the switch 71 is also eccentri- 75 cally pivoted the supporting rod 79 carrying the abutment 8O supported loosely on the rod by the spring 81 which in turn is 'car ried by the adjustable support 82 threaded to therod. In Fig. 3 the abutment 80 is 80 shown ina position ready for welding before the arc is. drawn. In'Fig'. 2 it is shown in the osition during welding. i

T 1e electro-responsive device or solenoid 83 is also shown connected in multiple with the carbon pile and solenoid 56, through tlie conductors 84 and 77. It is adapted to lift the bridge 76 from its normal position across contacts to cross connect contacts 85 during welding, to transfer the solenoid 83 from circuit 74 and contact spring 7 3 into circuit with contacts 85,'. conductor 86 and spring contact 87. l

In operation when the electrode 66 is brought into contact with the wort 67 and current is established through the welding circuit, current also passes through the solenoid 88, byway of the conductors 77 and 84 with the result that the core of the solenoid 8,8 is lifted, and the bridge 76 leaves the contacts 7 5 and cross connects. the contacts 85 leaving the solenoid in a circuit traced through the conductor 86 and spring 87 v which, when the switch 71 has been rotated, has been brought as described into connection with the swinging arm 72. In the circuit shown in Fig. 2 the bridge is in contact with the contacts 7 3 and the swinging arln 72 is in contact with the spring 87. This is the welding position.

The starting or normal position is shown inFig. 3. Before starting to weld the abutment 80 rests against the bottom of the lever 51, and the swinging" arm 72 is in contact with the spring 87 The circuit of 115 the solenoid l70 is opened, however, at the bridge 76 which is in -contact only lwith contacts 75. At this time the resistance of the pile is'sufcient when the arel is started,

to preventva rush of current. When the arc 12o is started, and -current energizes lthe coil 83 lifting the bridge 76.away :from the contacts 75, the brldgecrossconnects contacts 85,

throwing the current through the solenoid g 70, switch 71, arm 72, spring 87, conductor l86- cross connected `contacts 85, conductor 77 and conductor 62 bac-k to the generator. This energizes the coil 70, so that its core l. rotates the switch l71,`in a direction contrary to that of the hands-of vthe clock,

' dash pots may be swinging the arm 72 away from the spring 87 around 'into contact with the spring 73 thereby establishing at this point a new circuit for the solenoid circuit which is open at the contacts 75, thereby establishing the welding position. To prevent a too violent engagement between the arm 72 and the contact springs 73 and 87, the core 70u of the solenoid has threaded to it a rod 70", which passes through the top of the solenoid bracket 70d and is provided-with a nut 70. This nut comes down against the top of the bracket and arrests the movement of the switch 71. When the arc is broken between the terminals 66 and 67 the coil 83 is denergized releasing thebridge 76, so that it again cross connects contacts 75 thereby again closing the circuit of the solenoid 70, so 'that it is caused to operate in the reverse direction throwing its swinging arm 72 into contact with the spring 87, thus breaking the active welding circuit, and leaving thev apparatus ready to start.

Dash pots 88 and 89 may, if desired, be

employed to render .the oscillations ofthe.

lever more sluggish. The plungers of the secured suitablyy to brackets 90 and 91 respectively fixed to the panel 45, and their cylinders may be linked directly tothe lever 51 and the core 58 respectively, the core being linked to the lever 51. Oil or air or any fluid maybe employed in the dash pots which may be of ordinary well known construction. These dash pots are adapted to render the lever oscillatlons more suggish. Either or both may be used,

but they are not an essential feature-of this invention.

The spring 8'1 should have the right compression to.open the pile sufiicient y to increase its resistance suliciently to prevent the rush of current heretofore described.

. The weights may be varied until the proper adjustment is'arrived at.

The rheostat 460 may also be vairied, to vary the strength of the solenoid 56, and

. the rheostat and weights should be so varied as to properly coperate.

What I claim is i 1. In a welding system, a welding tool, a source of supply, a starting circuit' and an automatic resistance in multiple therewith operated by variations of resistance in the welding arc to maintain a current of even amperage, thereby maintaining an ev'en heating current at the arc.

.2. In a welding system, a weldingI tool, a source of current supply, a starting circuit, an automatic resistance operated by the variation of resistance inthe welding are to maintain an even flow of heating current and a manually operated rheostat adapted to supply an arbitrarily fixed ow of additional heating current to the welding tool.

3.` In a Welding system, a welding tool, va source of current supply, a starting circuit, an automatic resistance operated by the variation of resistance in the welding arc to maintain an even flow of heating current and a manuallyb operated rheostat adapted to supply arbitrarily, an additional fixed ilow of current tothe Welding tool,

located in a branch circuit around said automatic resistance.

4. .In a welding system, a Welding tool, a source of current supply, a starting circuit, an automatic resistance operated 'by the variation of resistance in the welding arc to maintain an even flow of heating' current and a manually operated rheostatadapted to supply arbitrarily an additional fixed flow of current to the welding tool, located in a branch circuit around said automatic resist ance and also in a branch circuit laround said starting circuit.

5. The method of maintaining an even flow of current in a welding arc having a variable resistance, which consists in automatically varying the flow of current in a branch circuit to counteract the variation of resistance in the welding arc, and in supplying through another branch circuit a fixed flow of current.

6. Inl an electric arc welding system, a

source of welding current, two welding' terminals, one consisting of a welding pencil or tool and the other consisting of the work to be operated upon thereby, and means in said circuit adapted to varv the resistance of the welding circuit excluding the arc substantially and inversely to the variations of resista-nce of the Welding arc, to maintain a `substantially even flow of welding current across the arc. y

7. In a weldingsvstem, a source of weld-` ing current, two welding elements, one consisting of 'a welding pencil or tool and the other consisting of the work to be operated upon thereby, and means to prevent spattering of metalv located in said circuit before said elements are brought into contact and vlocated between one of said elements and said source of current adapted -to reduce the nresistancecf saidwelding circuit and bring bringing said welding elements together intoplement adapted to suppl one of said elements` and said source of Weld-l ing current adapted to vary the resistance of sald circuit inversely to the variation of the arc resistance between said two elements.

9. In a weldingsystem, a welding implement adapted to supply welding metal across an are,V a source of current supply, a starting circuit,'and an vautomatic resistance in multiple therewith operated by variations in relsistance of the welding arc to maintain a current ot' even amperage and an even flow of welding metal across the arc. i

10. In a welding system, a welding implement zulapted to supply welding metal across an arc, a source of current supply, :vstarting circuit, an automatic resistance Operated by the variations of resistance in the welding are to maintain an even How of. hcatingcurrent and vaneven flow 'of welding metal across the arc, and a manually o erated rheostat ada ted to supply an ar itrary fixed iow of iea'ting current'to thelwelding implement.

11. In a Welding system, a Welding imweld-ing metal across an are; a source o a starting circuit, and an automatic resistance in multiple therewith operated by variations in resistance of ,the welding arc to maintain acurrent of even'amperage and an even How of'weldingmetal across the are, said automatic resistance with the arc'.

In ani electric are welding system', a A

prisin current supply,v

being in ,series source of current, a welding in`iplement`-r adapted to supply weldingl metal across the" are, means in series with t of weldin metal' across the. are, means fto prevent t einitialrush of. current,A and.r I means to remove the same. as the arc `1sL drawn. u y -v 13. An electric arc weldin system cornpri'sing a welding circuit inc uding a variable resistance in series with the weld, and an electro-responsivedevice also in series with the weld and responsivefto graduations in weiding-current strength to `gradually vary the said resistance 4to compensate for changes in the welding resistance. p

14. An electric arc weldingsystem eo1n. a welding circuit and a pressure-4 variab e resistance and electro-res onsive device both in series with the wel and Ywith each other, and' said electro-responsivedevice being arranged to vary the'pressure on said'l resistance in responsetp Iwelding-our- ,rent changes, to compensate for 'resistance `changes in the weld.' l

' Signed at New York inthe county of New n York andState of New Yorkv this 10th day of June A.'D. 1916. p p

l DAVID H. WILSON.

Witnesses:

MYRQN F. Hrm, -MARY W. WAamcE.-

e arc to vary the resistance of the welding lcircuit outside the j are, to compensate fork the`variations vof re'' sistance in said varc andto maintain r a lowvso i 

